On Mon, 28 Dec 2020, Tamar Christina wrote:
> Hi All,
>
> This fixes an issue where is_linear_load_p could return the incorrect
> permutation kind because it is singe pass.
>
> This arranges the candidates in such a way that there won't be any ambiguity
> so
> that the function can still be linear but give correct values.
>
> Bootstrapped Regtested on aarch64-none-linux-gnu, x86_64-pc-linux-gnu
> and no issues.
>
> Ok for master?
OK. I see no testcases in any of the patch in this series though.
Thanks,
Richard.
> Thanks,
> Tamar
>
> gcc/ChangeLog:
>
> * tree-vect-slp-patterns.c (is_linear_load_p): Fix ambiguity.
>
> --- inline copy of patch --
> diff --git a/gcc/tree-vect-slp-patterns.c b/gcc/tree-vect-slp-patterns.c
> index
> fede88923af8521ee4954c8ae27b0e589f975610..7fd79d91c6ba4ccdbf361307a6105fb7e46aa961
> 100644
> --- a/gcc/tree-vect-slp-patterns.c
> +++ b/gcc/tree-vect-slp-patterns.c
> @@ -140,32 +140,32 @@ is_linear_load_p (load_permutation_t loads)
>
> unsigned load, i;
> complex_perm_kinds_t candidates[4]
> - = { PERM_EVENODD
> - , PERM_ODDEVEN
> - , PERM_ODDODD
> + = { PERM_ODDODD
> , PERM_EVENEVEN
> + , PERM_EVENODD
> + , PERM_ODDEVEN
> };
>
> int valid_patterns = 4;
> - FOR_EACH_VEC_ELT_FROM (loads, i, load, 1)
> + FOR_EACH_VEC_ELT (loads, i, load)
> {
> - if (candidates[0] != PERM_UNKNOWN && load != i)
> + if (candidates[0] != PERM_UNKNOWN && load != 1)
> {
> candidates[0] = PERM_UNKNOWN;
> valid_patterns--;
> }
> - if (candidates[1] != PERM_UNKNOWN
> - && load != (i % 2 == 0 ? i + 1 : i - 1))
> + if (candidates[1] != PERM_UNKNOWN && load != 0)
> {
> candidates[1] = PERM_UNKNOWN;
> valid_patterns--;
> }
> - if (candidates[2] != PERM_UNKNOWN && load != 1)
> + if (candidates[2] != PERM_UNKNOWN && load != i)
> {
> candidates[2] = PERM_UNKNOWN;
> valid_patterns--;
> }
> - if (candidates[3] != PERM_UNKNOWN && load != 0)
> + if (candidates[3] != PERM_UNKNOWN
> + && load != (i % 2 == 0 ? i + 1 : i - 1))
> {
> candidates[3] = PERM_UNKNOWN;
> valid_patterns--;
>
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg,
Germany; GF: Felix Imendörffer; HRB 36809 (AG Nuernberg)
